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            <h2 class="title" style="clear: both"><a id="dbset_h_ffactor"></a>DB-&gt;set_h_ffactor()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB-&gt;set_h_ffactor(DB *db, u_int32_t h_ffactor);  </pre>
      <p>
         Set the desired density within the hash table.  If no value is
         specified, the fill factor will be selected dynamically as pages
         are filled.
    </p>
      <p>
        The density is an approximation of the number of keys allowed to
        accumulate in any one bucket, determining when the hash table grows or
        shrinks. If you know the average sizes of the keys and data in your
        data set, setting the fill factor can enhance performance. A reasonable
        rule computing fill factor is to set it to the following:
    </p>
      <pre class="programlisting">             (pagesize - 32) / (average_key_size + average_data_size + 8) </pre>
      <p>
         The <code class="methodname">DB-&gt;set_h_ffactor()</code> method configures a database, not only
         operations performed using the specified 
         <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a>  handle.
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         The <code class="methodname">DB-&gt;set_h_ffactor()</code> method may not be called after the 
         <a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a>  method is called. If
         the database already exists when <a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a>  
         is called, the information specified to <code class="methodname">DB-&gt;set_h_ffactor()</code> will be ignored.
    </p>
      <p>
         The <code class="methodname">DB-&gt;set_h_ffactor()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
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              <h3 class="title"><a id="idp50370888"></a>Parameters</h3>
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                <h4 class="title"><a id="idp50266472"></a>h_ffactor</h4>
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          <p>
                          The <span class="bold"><strong>h_ffactor</strong></span> parameter is the
                          desired density within the hash table.
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              <h3 class="title"><a id="idp50373888"></a>Errors</h3>
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        <p>
                         The <code class="methodname">DB-&gt;set_h_ffactor()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
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                <h4 class="title"><a id="idp50381872"></a>EINVAL</h4>
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                If the method was called after <a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a> 
                was called; or if an invalid flag value or parameter was specified.
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                <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a>  
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              <h3 class="title"><a id="idp50372776"></a>See Also</h3>
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                     <a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a> 
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